Electrical Engineering ⇒ Topic : Y-Parameter

y-PARAMETERS

These parameters are also known as short circuit parameters. In y-parameters, the input and output currents are expressed in terms of the input and output voltages. For a two-port network from Figure (1), it can be written as:

                             V₁ = Z₁₁I₁ + Z₁₂I_{2                      .................... (1)}

                              I₁ = Y₁₁V₁ +Y₁₂V_{2                     ...................... (2)}

and                        I₂ = Y₂₁ V₁ + Y₂₂V_{2                  ......................  (3)}

_{In the matrix form, Eqs. (2) and (3) can be written as:}

                                       .................... (4)

where y₁₁, y₁₂, y₂₁, and y₂₂ are known as y-parameters of a two-port network. For V₂ = 0, i.e.,output port is short-circuited, we get

                                                  ............. (5)

                                                ................. (6)

For V₁ = 0, i.e., input port is short-circuited, it can be obtained as:

                                                    .................... (7)

                                                   .................... (8)

y₁₁ and y₂₂ are known as input and output admittances when output and input ports are short-circuited, respectively, y₁₂ and y₂₁ are known as reverse and forward transfer admittances when input and output ports are short-circuited, respectively.